In the prior art, a method for positioning a mobile station mainly includes the following three types: Assisted Global Positioning System (AGPS) positioning, base station positioning and Wireless Fidelity (Wi-Fi) positioning. The above three positioning techniques have respective advantages and disadvantages, and also have different application scenarios.
AGPS technique is a technique for positioning a mobile station, which combines network information of a station and Global Positioning System (GPS) information, and it can be used in networks such as a Global System For Mobile Communications (GSM)/General Packet Radio Service (GPRS) network, a Wideband Code Division Multiple Access (WCDMA) network and a Code Division Multiple Access (CDMA) 2000 network.
Advantages of the AGPS solution mainly lie in its positioning accuracy, which is up to about 10 meters in a normal GPS operation environment in open areas such as outdoors, thus it is currently regarded as a positioning technique with the highest positioning accuracy. Another advantage of the technique is that a first capture time for a GPS signal is generally only several seconds, while the first capture time of GPS technique may be 2 to 3 minutes.
Though AGPS technique has a high positioning accuracy and a short first capture time for a GPS signal, it also has some disadvantages. Firstly, a problem regarding indoor positioning is still not well solved; secondly, the implementation of AGPS positioning needs multiple network transmissions, up to six unidirectional transmissions at most, thus occupying a large amount of on-the-air resources; in addition, AGPS technique requires an GPS receiver module to be added into a mobile terminal and an antenna of the mobile to be restructured, and devices such as a position server and a differential GPS reference station needs to be built on a mobile network. Since AGPS technique requires an GPS receiver module to be added into a mobile terminal, if a user wants to use an AGPS mobile positioning service, he/she has to replace his/her current mobile terminal with one having an GPS receiver module added therein.
A base station is a signal reception/transmission station for a mobile phone. Since a base station is built by an operator, the operator can acquire identification information of the base station, i.e., Location Area Code (LAC) and Cell Identifier (CID). When a mobile terminal is positioned, an LAC and a CID are transmitted to a remote server, which through triangulation calculation can perform positioning on the mobile terminal. The base station positioning is typically applied to a positioning service for 110 alarm, and can perform indoor positioning but with common accuracy, furthermore, the premises of positioning are that there must be mobile phone services.
Wi-Fi is a technique which can interconnect wirelessly a personal computer, a hand-held device and the like. Wireless routers are currently set in companies, shopping malls and homes, and they are Wi-Fi wireless hotspot devices. Similarly to the base station positioning, when positioning is performed through Wi-Fi, after finding globally unique identifiers of these Wi-Fi devices, i.e., Medium/Media Access Control (MAC) codes, a mobile terminal sends them to a remote server so as to perform positioning. The Wi-Fi positioning has common accuracy, and it can perform indoor positioning with premises that there must be Wi-Fi services.
In a positioning application for a mobile terminal, following three ways are used: 1. the above three positioning methods are performed simultaneously and a positioning result of each of the positioning methods is fed successively back to user so as to be processed accordingly; 2. only one of the three positioning methods is used to perform positioning; 3. after AGPS positioning fails, a positioning result from the base station positioning is used as a final positioning result.
For a user, each of the three ways has certain disadvantages: way 1 has poor user experiences, the user is only desirable to acquire an accurate positioning result instead of caring about positioning results made by respective methods; due to the use of only one positioning method, way 2 is only applied to some positioning scenarios, and in certain scenarios the use of only one positioning method may result in an inaccurate positioning result; compared with way 2, way 3 combines two types of positioning results, but since a result for an indoor positioning made by the base station positioning usually has great errors and in case of a non-indoor positioning the result usually depends on where a base station is located, such positioning results also have great errors.